Carton flap opener



April 9, 1968 J. c. BERNEY CARTON FLAP OPENER Filed March 1,

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United States Patent Gfiice 3,375,592 Patented Apr. 9, 1%68 3,376,692 CARTGN FLAP OPENER Joseph C. Berney, 2437 Bamboo St., Newport Beach, Calif. 92660 Filed Mar. 1, 1965, Ser. No. 435,869 13 Claims. (Cl. 53332) ABSTRACT OF THE DISCLOSURE A case fiap opener includes a blower which directs a jet of air under one side flap to partially raise that flap. The case is then shifted laterally and the blower directs an air jet under the other side flap to partially open that flap. A plow then engages the vertically opened side flaps and fully opens them as the case is conveyed on. Another blower directs a jet of air under the leading end fiap to partially open that flat and a traveling hook completes opening of the leading end fiat. A rotatably mounted stationary hook engages the trailing end flap and opens it.

Background of the invention This invention relates to apparatus for opening cartons and more particularly to apparatus for opening the four top flaps of a conventional shipping container having two end flaps and two side flaps, such as one made from cardboard, corrugated board, or the like.

Four-flap corrugated cases in conventional use as shipping containers are mainly of two general types commonly known as RSC (regular slotted containers) and AFM all flaps meet) containers. In AFM cases all of the top closure flaps meet when in the closed position; that it, the end flaps meet when folded together and the longitudinal side flaps meet when folded together. In the RSC type of case the side flaps and the end flaps are of the same width, so on elongate cases the side flaps meet but the end flaps do not meet when in the closed position. The present invention is directed toward apparatus for fully opening all of the top flaps of the RSC type of case, it being readily apparent that the side flap opening mechanism of the present invention will also open the side flaps of the AFM type of case.

In modern canning and bottling plants the unloading of cans or bottles from shipping cases is accomplished mechanically. The cases of empty bottles or cans are typically received in an assembled configuration with the bottom flaps sealed and the top flaps unsealed but in a closed condition. Therefore, the cartons are passed through apparatus which fully opens their top flaps, the opened cartons then being fed directly to the apparatus for unloading them.

The typical prior art flap opening apparatus requires that the cartons be fed to the unloader apparatus in spaced relationship, the operation of various components of the apparatus being programmed as a function of time. This technique is not without attendant disadvantages. Relatively complex and costly apparatus and circuitry is required to maintain the necessary synchronization between carton spacing and the machine operating cycle. Also, the necessity for time synchronization in this technique is the dominant factor in determining the maximum feed rate of cartons into the flap opening apparatus, and hence into equipment located downstream from the flap opening apparatus. Furthermore, if a carton is not properly processed by the apparatus and is not discharged from the apparatus at the proper time, the apparatus must be shut down to prevent a jam-up and to allow correction. The present invention is directed toward flap opening apparatus which obviates the aforementioned disadvantages.

In accordance with the present invention technique the various operational components of the flap opening apparatus are functionally synchronized, rather than time synchronized. That is, the operation of the various components of the present invention apparatus is controlled by movement of the cartons to various positions in the apparatus. The present invention apparatus includes a novel side flap opening mechanism comprising means for momentarily arresting motion of a carton and partially opening one of its side flaps, means for theih' moving the carton laterally and partially opening its other side flap, and means for then feeding the carton into a plow which fully opens the side flaps. The carton then is presented to an end flap opening mechanism comprising traveling hook means for opening the leading end flap and rotatably mounted, stationary hook means for engaging the trailing end flap, movement of the carton away from the stationary hook causing the trailing end flap to be opened.

The elimination of time synchronization circuitry and equipment results in a much simpler and less expensive apparatus. Elimination of the necessity for maintaining any certain spacing, or any spacing at all, between cartons fed into the present invention apparatus enables a significantly faster feed rate .as compared with prior art apapratus. The present invention flap opening apparatus is capable of a higher feed rate than that of other material handling equipment commonly used in packaging and bottling plants, whereby the feed rate of the flap opening mechanism will not determine the flow rate of materials through the plant. Should a malfunction occur in the present invention apparatus whereby cartons are not discharged from the apparatus, there is no interruption of a timed sequence and hence no necessity for a complete shut-down and resynchronization.

Accordingly, it is an object of the present invention to provide improved carton top flap opening apparatus.

It is also an object of the present invention to provide an improved carton top flap opening apparatus capable of a high feed rate.

It is another object of the present invention to provide a relatively simple and inexpensive carton top flap opening apparatus.

It is a further object of the present invention to provide a carton top flap opening apparatus in which there is no necessity for maintaining spacing between cartons fed into the apparatus.

It is still another object of the present invention to provide a completely automatic carton top flap opening apparatus which is not programmed as a function of time.

It is a yet further object of the present invention to provide improved carton top flap opening apparatus in which synchronization is accomplished by the movement and positioning of cartons passing through the apparatus.

It is also an object of the present invention to provide an improved apparatus for opening the longitudinally extending top flaps of cartons.

It is yet another object of the present invention to provide an improved apparatus for opening the top end flaps of cartons.

t is a still further object of the present invention to provide improved flap opening apparatus wherein the opened cases may be held for release to downstream equipment in automatic synchronization with the need for cases by the downstream equipment.

The novel features which are believed to be characteristic of the invention, both as to its organization and method of operation, together with further objects and advantages thereof will be better understood from the following description considered in connection with the accompanying drawing in which a presently preferred embodiment of the invention is illustrated by way of example. It is to be expressly understood, however, that the drawing is for the purpose of illustration and description only, and is not intended as a definition of the limits of the invention.

In the drawing:

FIGURE 1 is a plan view of a machine constructed in accordance with the present invention;

FIGURE 2 is a view taken along the line 22 of FIG- URE 1;

FIGURE 3 is a partial perspective view of the side flap opening mechanism of the machine of FIGURE 1;

FIGURE 4 is a partial perspective view showing the side flap opening mechanism in operation;

FIGURE 5 is a pictorial view of a case, depicting operation of the end flap opening mechanism of the apparatus of FIGURE 1;

FIGURE 6 is a perspective view of an air blower head used in the side fiap opening mechanism of the apparatus of FIGURE 1;

FIGURE 7 is a view taken along the line 77 of FIG- URE 6;

FIGURE 8 is a view taken along the line 88 of FIG- URE 6; and

FIGURE 9 is an? electrical schematic diagram of the control circuit for the apparatus of FIGURE 1.

Referring now to the drawing, in FIGURES l and 2 there are shown plan and elevation views of a presently preferred embodiment of case opening apparatus utilizing the present invention concepts For ease of explanation the machine may be functionally divided into a side flap opening mechanism A and an end flap opening mechanism B. The description of these mechanisms will be preceded by a general description of the complete machine and followed by explanations of the control circuit and operating cycle.

General description An infeed conveyor 10 feeds the cases to be opened to the machine, and a transfer conveyor 11 is provided to transfer cases leaving the machine to an outfeed conveyor, not shown. A main conveyor 20 extends longitudinally through the machine and is slightly offset from the infeed and transfer conveyors, as can be best seen in the plan view of FIGURE 1. In the illustrated embodiment it is not necessary that the transfer conveyor 11 be offset from the main conveyor 20; however, it is shown offset for the purpose of indicating how the operation of the present invention apparatus can be synchronized with the operation of other carton handling equipment by operating the transfer conveyor belt at a faster speed than the main conveyor belt to speed up the cases as they are discharged from the present invention apparatus. The conveyors 10, 11 and 20 are in coplanar parallel alignment and in the illustrated embodiment are of the driven endless belt type, although various other types of conveyors, such as the roller type, are suitable. The infeed conveyor 10 comprises an endless belt 13 looped over a pulley 14 and another pulley, not shown, supported by side rails 15 and 15a. The transfer and main conveyors are similarly constructed, the transfer conveyor 11 having an endless belt 16 passing over a plurality of pulleys 17 and an intermediate support plate, the main conveyor 20 having an endless belt 21 passing over pulleys 22 and in intermediate support plate 18. One or more of the pulleys of each of the conveyors are driven by a suitable mechanism, not shown, so that the uppermost belt run of each of the conveyors moves in a left-to-right direction in the drawing. The three conveyors are spaced closely together so that cartons leaving one conveyor will be picked up by the next succeeding conveyor. Cases leaving the infeed conveyor 10 are deposited by their own movement on the upper belt run of the main conveyor 20 and are first presented to the side flap opening mechanism A.

The side flap opening mechanism A, the end flap openof the carton into a plow which completely opens the side flaps. The end flap opening mechanism B, which will also be hereinafter described in detail, includes means for again arresting motion of the carton, opening its leading end flap, laterally moving the carton into central alignment on the belt of the transfer conveyor while bringing a hook into engagement with the trailing end flap, and then resuming longitudinal movement of the carton whereby movement of the carton will result in the trailing end flap being opened by the hook. Upon leaving the transfer con-:

veyor 11 the opened carton is removed from the machine by suitable outfeed conveyor means, not shown.

Side flap opener The side flap opener A comprises a side fiap blower bar 25, a plow 29, a case positioning mechanism generally in dicated by the reference numeral 30, and a movable guide apparatus generally indicated by the reference numeral 40.

The base of the case positioning mechanism 30 is an L- shaped bracket 31 mounted to the supporting framework 19 near the front end of the main conveyor 20. The base leg of the bracket 31 defines a stop bar 32 and, as can best be seen in FIGURE 1, the bracket 31 is disposed so that the stop bar 32 is in perpendicular alignment with the conveyor belts, The case positioning mechanism 30 and an opposing guide apparatus 40 are mounted on laterally movable side bars 201 and 202 respectively.

The movable portions of the side flap opener and end flap opener of the present invention apparatus are operated by air pressure, the apparatus employing various,

combinations of air cylinders commonly known as double acting cylinders, as distinguished from single acting air cylinders. The term single acting air cylinder refers to an air cylinder having its piston rod normally urged by spring pressure to its withdrawn position, application of air pressure to the head end of the cylinder causing the piston rod to move against the spring pressure to an extended position projecting a maximum distance from the cylinder body, the spring pressure returning the piston rod to its withdrawnposition upon subsequent release of air pressure from the cylinder body. The term double acting air cylinder herein refers to an air cylinder in which air pressure can be supplied to either the head end or the rod end of the cylinder, there being no internal spring loading of the piston rod. Thus, to urge the piston rod to its withdrawn position, air pressure is applied to the rod end of the cylinder, the head end being relieved to atmospheric pressure. Conversely, to urge the piston rod to its extended position, air pressure is applied to the head end of the cylinder, the rod end being relieved to the atmospheric pressure. Control of the air pressure applied to both the single acting and double acting types of air cylinders enables selective movement of structural assemblies secured to the projecting ends of the piston rods, this control being achieved through the use of solenoid-operated 3-way and 4-way air valves. Such air valves are well known in the art and hence will not be described in detail. Although the operation of the air parallel alignment with the first stop bar 32. An L-shaped bracket 35 has an elongate leg portion 35a defining a pusher bar and a shorter base leg portion 35b defining a second stop bar. The pusher bar portion 35a of the L- shaped bracket 35 is secured to the projecting end of the piston rod 34 of the air cylinder 33. Strength and stability during movement of the bracket 35 in accordance with movement of the piston rod 34 is achieved through the use of a pair of cylindrical support rods 36 which project from the pusher bar portion 351: and pass through suitable guide sleeves formed in the elongate leg portion of the bracket 31. Thus, the bracket 35 is selective movable transverse to the conveyor belts and longitudinal axis of the machine, from a retracted posit-ion as shown by the solid lines in FIGURE 1 to an extended position indicated by dashed lines in FIGURE 1.

The movable guide apparatus 40 consists of a double acting air cylinder 4-1 having a support plate 43 secured to the projecting end of its piston rod 42. The air cylinder 41 is mounted to the side bar 202 on the opposite side of the main conveyor from the case positioning mechanism 30. The piston rod 42 of the air cylinder 41 is in perpendicular alignment with the conveyor belts and extends through an aperture in an upstanding guide rail 23 which extends longitudinally along the side bar 202. A guide rail 24 extends longitudinally along the side bar 201 the guide rail 24 extending between the case positioning mechanism 30 and another case positioning mechanism 50. The leading end of the guide rail 23 defines an outwardly curved portion 23a adjacent the input end of the main conveyor 24 the purpose of the guide rails 23 and 24 being to maintain proper alignment of cases moving forward on the main conveyor.

The supporting framework 19 supports a vertically movable channel 19a to which is mounted the plow 29 and various other components. The plow 29 is mounted in a dependent position to the overhead channel 19a by means of support bars 27 and 28. The side flap blower bar is mounted to the underside of the plow 29 in a position ofi center with respect to the conveyor belt 21 of the main conveyor, and toward the case positioning mechanism 30, as can best be seen in FIGURE 1. The nose of the plow 29 defines a downwardly turned portion 29:: which is partially cut away to allow passage of the side flap blower bar 25. The projecting end of the side flap blower bar defines a skewed end portion 26 which extends angularly upward and away from the main conveyor belt 21.

An air blower head 44 is mounted to the side flap blower bar 25 in a position generally opposite the carton positioning mechanism 30. As can best be seen in the various views of FIGURES 6, 7 and 8, one of the longitudinal side surfaces of the blower head 44 is substantially vertical while its other longitudinal side surface is angularly inclined. The blower head 44 is provided with a main interior passageway 45 which is connected through a suitable air line and control valve, not shown, to a source of air pressure. A series of air distribution passageways 4649 are in communication with the main interior passageway 45 of the blower head 44 and terminate in orifices in the various surfaces of the blower head, thereby defining an air distribution manifold. Referring specifically to FIGURE 7, the air distribution passageway 46 is directed angularly downward and extends laterally from the main interior passageway 45 and terminates in an orifice at the junction between the vertical side and bottom surfaces of the blower head, andv the air distribution passageway 47 is also directed angularly downward and extends laterally from the main interior passageway 45 and terminates in an orifice in the bottom surface of the blower head.

Referring specifically to FIGURE 8, the air distribution passageways 48 and 49 are horizontally directed and extend laterally away from the main interior passageway 45, the passageway 48 terminating in an orifice in the vertical side surface of the blower head, and the passageway 49 terminating in an orifice in the angularly inclined side surface of the blower head. Upon the selective application of air pressure to the air distribution manifold of the blower head 44, four air jets will be established which, in conjunction with controlled movement of a carton disposed beneath the air blower head, will sequentially, partially open the side flaps of the carton, as will be hereinbelow explained.

End flap opener The end flap opener B comprises a case positioning mechanism generally indicated by the reference numeral 50, an opposing guide apparatus generally indicated by the reference numeral 60, a trailing end flapopening mechanism generally indicated by the reference numeral 70, and a leading end flap opening mechanism. generally indicated by the reference numeral 80. The case positioning mechanism 50 and the opposing guide apparatus 60 are respectively identical to the hereinab-ove described case positioning mechanism 30 and movable guide apparatus 40. The base'of the case positioning mechanism 50 is an L-shaped bracket 51 mounted to the side bar 201 near the rear end of the main conveyor 20. The base leg of the bracket 51 defines a stop bar 52 disposed in perpendicuiar alignment with the conveyor belt and extending over a portion of the main conveyor belt 21 into the path of a case moving on the main conveyor belt.

A double acting air cylinder 53 is mounted to the elongate leg portion of the bracket 51 with its piston rod 54 projecting through a suitable aperture therein and in parallel alignment with the stop bar 52. An L-shaped bracket 55 has an elongate leg portion 55a defining a' pusher bar and a shorter base leg portion 55b defining another stop bar. The pusher bar portion 55a of the L-shaped bracket 55 is secured to the projecting end of the piston rod 54' of the air cylinder 53, the elongate leg portion of the bracket 51 being provided with guide sleeves through which extend a pair of cylindrical support rods 56 projecting from the pusher bar port-ion 55a.

The opposing guide apparatus 60 consists of a double acting air cylinder 61 having a support plate 63 secured to the projecting end of its piston rod 6 2. The air cylinder 61 is mounted on the side bar 202 on the opposite side of the main conveyor from the case positioning mechanism 50 for coaction therewith in a manner to be hereinbelow explained.

The trailing end flap opening mechanism includes an elongate hook 71, a double acting air cylinder 72 having a piston rod 73, and a crank arm 74. The crank arm 74 is rotatably mounted by rigidly securing it to a shaft 75 journaled within a pair of support brackets 76 depending from the overhead channel 19a. The hook 71 is also rigidly secured to the shaft 75 for movement with the crank arm 7 4. The air cylinder 72 is pivotally mounted between a pair of support brackets 79 depending from the overhead portion 190 of the supporting framework. The projecting end of the piston rod 73 of the air cylinder 72 is rotatably secured to the free end of the crank arm 74. One end of a helically wound coil spring 77 is secured to a mounting bracket 78, the other end of the coil spring being secured to an intermediate portion of the crank arm 74.

The hook 71 is normally maintained in the raised position shown in FIGURE 2 by the selective application of air pressure to the rod end of the air cylinder 72, which maintains the piston rod inits fully retracted position. Upon selectively relieving the air pressure from the air cylinder 72 the spring tension of the coil spring 77 causes counterclockwise rotation of the crank arm 74 and lowers the hook 71 in front of and slightly below the leading edge of the trailing end flap, as indicated by the dashed lines in FIGURE 2.

The leading end flap opening mechanism 80 includes a double acting air cylinder 81 having a piston rod 82 to which is rotatably mounted a rigid arm assemblage generally indicated by the reference numeral 85. The air cylinder 81 is mounted in horizontal alignment over the main conveyor belt 21 by means of a pair of support brackets 83 depending from the overhead portion 19a of the supporting framework.

The arm assemblage 85 comprises a bent lower arm 86 the upper end of which is rigidly secured to a shaft 88, and an upper arm 87 one end of which is rigidly secured to the shaft 88 and in substantially perpendicular alignment with the upper portion of the lower arm 86. The arm assemblage 85 is rotatably mounted by journaling the shaft 88 within a clevis 89 secured to the projecting end of the piston rod 82. Projecting laterally from the other end of the upper arm 87 is a cylindrical follower roller 84. An elongate guide block 90 is mounted to the overhead channel 19a, the guide block 90 defining an elongate curved guide slot 91. The follower roller 84 of the arm assemblage is fitted within the guide slot 91 of the guide block and, upon extension of the piston rod 82 by a pplication of air pressure to the head end of the air cylinder 81, the arm assemblage 85 will move from left to right with a rocking type motion (the path of the lower arm portion being generally indicated by the dash line arrows in FIG- URE 2). An air line terminating in a jet nozzle 92 is connected to the source of air pressure, the nozzle 92 being disposed adjacent the tip of the bent lower arm 86 when the arm is in its normal rest position shown in solid lines in FIGURE 2.

Disposed at the end of travel of the leading end flap opening mechanism 70 is a flap retaining mechanism generally indicated by the reference numeral 95. The fiap retaining mechanism 95 includes an elongate flap retaining member 93 having an upwardly curved end portion 94 to which is rotatably mounted a lever arm 96. The lever arm 96 is normally urged in a clockwise direction against an adjustable stop 97 by a tension spring 98 which is secured between the upper end of the lever arm 96 and a mounting bracket 99 secured to the elongate member 93.

Control circuit Synchronized actuation of the various air cylinders in the illustrated embodiment is accomplished through the use of six limit switches, indicated by the reference characters LS-l through LS6. The locations of the various limit switches are shown in FIGURES 1 and 2 of the drawing. Switch LS-1 is a normally open switch and is positioned adjacent the case positioning mechanism 30 in such a manner that the switch will be closed by a case coming into contact with the stop bar 32. The switch LS-2 is a normally open switch disposed adjacent the opposing guide apparatus 40 in such a manner that the switch will be closed by lateral movement of a case on the main oonveyor 20. LS-3 is a normally open switch disposed adjacent the case positioning mechanism 50 in such a position that the switch will be closed by a case contacting the stop bar 52. LS-4 is a normally closed switch disposed along an edge of the transfer conveyor 11 and arranged so that a case traveling along the transfer conveyor 11 will open the switch. LS- and LS-6 are normally open switches mounted to opposite ends of the elongate guide block 90. The limit switch LS5 is adjusted for actuation by the end of the arm assemblage 85 when the piston rod 82 reaches its fully extended position. The switch LS-6 is mounted so that it will be closed by the follower pin 84 when the piston rod 82 reaches its fully retracted position.

Referring now to FIGURE 9 of the drawing there is shown an exemplary electrical circuit for use with the illustrated embodiment. Electrical switching is accomplished by the limit switches and a double pole relay having a coil 104, a set of normally closed contacts with terminals 111 and 112, and a set of normally open contacts with terminals 113 and 114. Air switching is accomplished by five solenoid-operated air valves. An air valve having a solenoid 101 is provided for the selective switching of air to the air blower head 44. An air valve having a solenoid 102 is provided for the selective switching of air to the air cylinders 33 and 41. An air valve having a solenoid 103 is provided for the selective switching of air to the air cylinder 81.An air valve having a solenoid 105 is provided for the selective switching of air to the air cylinders 53 and 61. An air valve having a solenoid 107 is provided for the selective switching of air to the air cylinder 72. The air lines interconnecting the air valves electrical junction 115. The solenoid coils 101 and 102 I are each connected between the electrical junction 115 and the bus bar 109. One contact of the switch LS-3 is connected to the bus bar 108, the other switch contact being connected to the relay contact terminal 111. The.

solenoid 103 is connected between the bus bar 109 and the relay contact terminal 112. One contact of the switch LS5 is connected to the bus bar 108, the other switch contact being connected to an electrical junction 116.

The relay coil 104 is connected between the electrical junction 116 and the bus bar 109.

One contact of the switch LS-4 is connected to the bus bar 103, the other switch contact being connected to the relay contact terminal 113, the relay contact terminal 114 being connected to the electrical junction 116. The

switch LS-6 and the solenoid 105 are connected in series between the electrical junction 116 and the bus bar 109. The solenoid 106 is connected between the electrical junction 116 and the bus bar 109.

Operating cycle The operating cycle of the illustrated embodiment of the present invention apparatus will be described by tracing the passage of a carton 100 through the apparatus,

the carton 100 being shown in FIGURE 1 in a starting position labeled A--1. Successive positions of the carton are labeled A--2, A-3, B-l, B-2, and B-3, the carton 100 i being indicated by phantom lines in these subsequent 1 positions.

In the starting position A--1 the carton 100 is shown in FIGURES 1 and 2 as approaching the end of the infeed conveyor 10. In this starting position, and assuming that there are no other cartons in the apparatus, the operational components of the apparatus are in their normal rest positions. In the normal rest position air pressure is applied to the rod ends of the air cylinders 33 and 53 so that the case positioning mechanisms 30 and 50 are in the positions shown in FIGURE 1. Air pressure is applied to the head ends of the air cylinders 41 and 61 so that the support plates 43 and 63 are in their maximum extended positions shown in FIGURE 1. In the normal rest position air pressure is applied to the rod end of the air cylinder 81 so that the arm assembly is in the position indicated by the solid lines in FIGURE 2. In the normal rest position of the air cylinder 72 air pressure is applied to its rod end so that its piston rod 73 is withdrawn, thereby maintaining the hook 71 in the raised position indicated by the phanom lines in FIGURE 2.

As the carton leaves the infeed conveyor 10 it is picked up by the main conveyor 20, the carton 100 being in an offset position with respect to the belt 21, as indicated in FIGURES 1, 3 and 4 of the drawing. Consequently, as the carton 100 passes under the side flap blower bar 25, the blower bar and the blower head will be positioned over the left hand longitudinal side flap of 9 the carton as it is viewed in FIGURES 3 and 4 of the drawing. As the carton 100 passes beneath the blower bar 25, the blower bar 25 presses the left hand flap down- Wardly to a closed position.

As the leading end of the carton 100 approaches the stop bar 32- and reaches the position A2 the carton closes the normally open switch LS-1. As can be seen from the circuit diagram of FIGURE 9, closing of the switch LS-1 completes the electrical circuit to the solenoids 101 and 102, actuation of the blower solenoid 101 resulting in the application of air pressure to the blower head 44 and actuation of the solenoid stop 102, thereby switching the air to the cylinders 33 and 41. Switching of the air pressure to the head end of the air cylinder 33, combined with relief of pressure in the rod end of the cylinder to the atmosphere in accordance with the usual operation of solenoid actuated air valves, causes extension of the piston rod 34 and movement of the L-shaped bracket 35 toward the air cylinder 41. Switching of the air to the air cylinder 41 results in withdrawal of its piston rod so that the support plate 43 moves substantially in unison With the L-shaped bracket 35. The case positioning mechanism 30 pushes the carton 100 laterally from position A-2 to the position A-3, the support plate 43 serving to prevent rotational movement of the carton which would otherwise be caused by movement of the main conveyor belt 21.

As the carton 100 is being moved from position A-2 to position A-3 air jets are being blown from the various passageways of the blower head 44. The air jet emerging from the passageway 47 is downwardly directed into the carton and causes the right hand side flap of the carton to be slightly raised. Slight raising of the right hand side flap causes the air jet emerging from the passageway 49 of the blower head to strike the underside of this side flap and to hold the side flap in a slightly raised position as the carton is undergoing lateral movement. Lateral movement of the carton with its right hand side flap slightly raised will cause the angularly inclined surface of the air blower head 44 to come into contact with the underside of the right hand side flap as the carton approaches the position A-3. The switch LS-Z is so arranged that lateral movement of the carton will close this switch before the carton breaks contact with the switch LS-l. Therefore, switch LS-2 closes prior to opening of the switch LS-1 to prevent interruption of the lateral movement of the carton and blowing of the air jets.

As the carton 100 is moved to the position A-3 which is in substantial alignment directly over the conveyor belt 21, the blower bar 25 slides under the right hand side fiap of the carton. As soon as the left side of the carton clears the blower head 44 the air jet emanating from the passageway 46 of the blower head will be directed downwardly into the left hand side of the box to slightly open the left hand flap (this flap no longer being held in a closed position by the blower bar 25). Slight raising of the left :hand side flap allows the air jet emanating from the passageway 48 of the blower head to strike the underside of this flap to thereby maintain this flap in a slightly open position.

During lateral movement of the carton 100 from the position A-2 to the position A-3 longitudinal movement of the carton along the main conveyor is prevented by the stop bar 32, acting in conjunction with the support plate 43. As the carton reaches the position A-3 it then clears the stop bar 32 and it starts moving longitudinally along the main conveyor in accordance with the movement of the conveyor belt 21, both of the side flaps being held in a slightly open position, the left side by air jets and the right side riding over the bar As the carton 100 moves from position A-3 and begins its longitudinal movement through the machine it is maintained in alignment between the guide rails 23 and 24 which are mounted to the side bars 201 and 202. It is presently preferred to provide for synchronized lateral adjustment of the positioning of the side bars in order to accommodate cases of difierent widths, and to provide for vertical adjustment of the channel 19a in order to accommodate cases of different heights. All during the time that the carton 100' was in the positions A-2 and A-3 the trailing end of the carton prevented a next succeeding carton from entering the machine. As the carton 100 leaves the position A-3, the solenoids 101 and 102 still being energized due to maintenance of the limit switch LS2 in its closed position, a next succeeding carton will come into contact with the stop bar 35b and its motion will be arrested. Continuing longitudinal movement of the carton 100 brings the undersides of its side flaps into contact with the nose portion 29a of the plow 29, further movement of the carton along the main conveyor resulting in complete opening of the side flaps by the plow 29.

When the carton 100 has proceeded down the main conveyor 20 a sufiicient distance to release the switch LS-2, this switch returns to its normally open position, thereby deenergizing the solenoids 101 and 102. Deenergization of the solenoid 101 turns off the air to the blower head 44, and deenergization of the solenoid 102 returns the piston rods of the air cylinders 41 and 33 to their normal rest position (as shown by the solid lines in FIGURE 1).

Return of the case positioning mechanism 30 moves the stop bar 3511 out of the way of the next succeeding carton to allow it to move into contact with the stop bar 32 and depress the limit switch LS1 to thereby begin another cycle of operation of the side flap opening mechanism A. The carton 100 then moves farther along the main conveyor and is presented to the end flap opening mechanism B with the side flaps of the carton fully open.

As the carton 100 reaches the position B-1 as indicated by the phantom lines in FIGURES 1 and 2 the front end of the carton depresses the normally open limit switch LS-3 to switch it to a closed position. As can be seen from the schematic diagram of FIGURE 9, closing of the switch LS3 will result in energization of the arm solenoid 103, energization of the arm solenoid 103 causing the application of air to the head end of the air cylinder 81 and relief of the pressure in its rod end to the atmosphere to thereby result in extension of the pistonrod 82. As the leading end flap of the carton 100' clears the bent lower arm 86 the air jet from the nozzle 02 is directed angularly downward into the front end of the carton, the air pressure causing the leading end flap of the carton to be slightly raised. As the piston rod 82 moves toward its fully extended position the bent lower arm 86 of the arm assemblage engages the underside of the leading end flap of the carton and rotates it clockwise to a fully opened position. As the piston rod 82 moves to its fully extended position the follower roller 84 follows the contours of the guide slot 91, thereby causing a rocking as well as translational movement of the arm assemblage 85 whereby the bent lower arm 86 will follow the path indicated by the phantom line arrows in FIGURE 2 of the drawing. This rocking motion of the bent lower arm 86 causes it to raise as it is passing over the leading edge of the carton and then lower to push the leading end flap into the fully open position. Throughout this operation the carton is maintained motionless in the position B1 since movement of the carton is impeded by the stop bar 52 of the case positioning mechanism 50.

When the leading end flap opening mechanism 80 is in its rest position the follower pin 84 holds the normally open limit switch LS-6 in a closed position. As the piston rod 82 begins to move to its extended position upon energization of the arm solenoid 103, the follower roller 84 moves away from the switch LS-6 allowing it to open to thereby provide a safety feature as will hereinbelow be explained.

As the piston rod 82 reaches its fully extended position the leading end flap of the carton having been opened 11 by the arm assemblage 85, the follower roller 34 actuates the normally open limit switch LS-S. As can be seen in the schematic diagram of FIGURE 9, closing of the switch LS-S results in energization of the relay coil 104 and of the hook solenoid 106, energization of the stop solenoid 105 being prevented at this time by the open condition of the switch LS-6. Energization of the relay coil 104 interrupts contact between the terminals 111 and 112 and establishes electrical contact between the relay terminals 113 and 114. Disruption of the electrical connection between the relay terminals 111 and 112 causes deenergization of the arm solenoid 103, thereby again switching the air to the cylinder 81 and returning the piston rod 82 to its normal rest position and withdrawing the arm assemblage 85.

As the leading end flap of the carton 100 is swung to its fully open position by the arm assemblage 85, the flap momentarily depresses the lower end of the lever arm 96 causing the lever arm to be rotated in a counterclockwise direction. As the flap clears the lower end of the lever arm 96 the tension of the coil spring 98 causes clockwise rotation of the lever arm back to its rest position against the stop 97, the flap retaining mechanism 95 being shown in this rest position in FIGURE 2. Thus. the fiap retaining mechanism 95 prevents the natural resiliency of the leading end flap from tending to rotate the flap toward the closed position upon withdrawal of the arm assemblage 85.

As the arm assemblage 85 begins to return to its normal rest position in accordance with the withdrawal of the piston rod 82, the limit switch LS-" returns to its normally open position to prevent oscillation of the arm assemblage 85 which would otherwise result. However, note that due to energization of the relay coil 104, the electrical potential from the bus bar 108 will still appear at the terminal 116 because of the electrical connection established between the relay contacts 113 and 114. Hence, opening of the switch LS-5 will not cause deenergization of the relay coil 104 nor of the hook solenoid 106.

Initial energization of the hook solenoid 106 switches the air to the air cylinder 72 and causes movement of the piston rod 73 to a fully extended position, thereby allowing the tension of the coil spring 77 to cause clockwise rotation of the hook '71 (see FIGURE 2) from the phantom line position downwardly to the solid line position wherein the hook 71 engages the trailing end flap of the carton 100.

Return of the piston rod 82 to its withdrawn position as shown in FIGURE 2 causes the follower roller 84 to close the normally open limit switch LS-6, thereby energizing the stop solenoid 105. Energization of the stop solenoid 105 causes the switching of air to the air cylinder 53 and 61 to actuate the carton positioning mechanism 50 and the movable guide apparatus 60 and cause its operation in a manner similar to that hereinabove eX- plained with reference to the case positioning mechanism and the movable guide apparatus 40.0f the side flap opening mechanism A. Actuation of the case positioning mechanism and the movable guide apparatus results in lateral movement of the carton 100 from the position B-l to the position B-2, correct alignment of the carton during lateral movement being maintained by the contact of the stop bar 52 and the support plate 63 with the carton. During lateral movement of the carton the hook 71 is maintained in engagement with the trailing end flap of the carton, the edge of the flap sliding along the curved end of the book. As the carton 100 reaches the position B-2 the leading end of the carton clears the stop bar 52, thereby allowing resumption of longitudinal movement of the carton. Longitudinal movement of the carton 100 moves the carton away from the hook 71, the spring pressure from the coil spring 77 maintaining the curved end of the hook in engagement with the trailing end flap to allow the trailing end flap 12 to be raised as the carton moves longitudinally away from the hook.

As the carton 100 leaves the main conveyor 20 it is picked up by the transfer conveyor 11 which carries the opened car-ton away from the present invention apparatus. As the carton 100 moves along the transfer conveyor belt 16 the carton will open the normally closed limit switch LS-4 and disrupt the connection between the bus bar 108 i and the junction point 116 (the switch LS-S being in its normally open position), thereby deenergizing the relay coil 104 and the solenoids 105 and 106. Deenergization of the stop solenoid 105 again switches the air to the air cylinders 53 and 61 and returns the case positioning mechanism 50 and the movable guide apparatus 60 to their respective rest positions shown in FIGURE 1. Deenergization of the hook solenoid 106 again switches the air to the cylinder 72 to cause withdrawal of its piston rod 73, thereby resulting in counterclockwise rotation of the hook 71 to the uppermost raised position shown by the phantom lines in FIGURE 2. Thus, upon opening of the switch LS-4 the end flap opening mechanism B is reset and is placed in readiness to open the end flaps of the next succeeding carton. When the carton 100 has passed far enough down the transfer conveyor 11 the switch LS-4 returns to its normally closed position. However, since the relay coil 104 has been deenergized, electrical contact between the terminals 113 and 114 is now interrupted so that closing of the switch LS-4 does not reenergize the relay coil 104 or the solenoids 105 1 and 106. These solenoids and relay coil :are reenergized by closing of the switch LS-S upon opening of the leading end flap of the next succeeding carton presented to the end flap opening mechanism.

Thus there has been described a presently preferred embodiment of apparatus for opening the four top flaps of RSC cases. Although the invention has been described with a certain degree of particularity, .it is understood that the present disclosure has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed. For exampe, although in the illustrated embodiment the cases are automatically discharged from the end flap opening mechanism in response to actuation of the switch LS-6 by return of the arm assemblage 85, the switch LS-6 could alternatively be located in other equipment located downstream from the present invention appartus, whereby discharge of cases from the present -in-;

vention apparatus can be synchronized with the operation of the other equipment. Also, although the illustrated embodiment of the side flap opening mechanism A and the end flap opening mechanism B imparts lateral movement to the cases, in some applications lateral .case movement is unnecessary. It is presently preferred to impart lateral movement to the cases so that the present invention apparatus may be utilized with various types of infeed and outfeed apparatus other than the infeed and I transfer conveyors shown.

What is claimed is:

1. Flap opening apparatus for rectangular cases of the type provided with closure flaps hinged to the top edges of each wall, said apparatus comprising, incombination:

(a) Conveyor means for advancing the cases in an upright position with their closure flaps foldedinward in at least partial overlapping relation;

(b) Plow means disposed over said conveyor means to engage the side closure flaps on :the case walls extending parallel with the conveyor travel when such flaps are in a partially raised position;

(0) A side fiap opening mechanism ahead of'said plow means for partially raising the side closure fiaps of the cases, said mechanism including means for partially opening one of the case side closure flaps and (d) An end fiap opening mechanism behind said plow means, said end flap opening mechanism comprising 14 downward into the case beneath said one side flap as the other side flap rides up over said elongate rod to thereby cause partial opening of said one side flap, and means for then releasing said case to allow traveling hook means for opening the leading end it to be carried by said conveyor means into said closure flap of a case emerging from said plow plow means; and

means, and rotatably mounted stationary hook means (e) An end flap opening mechanism behind said plow for engaging the trailing closure end flap of the means, said end flap opening mechanism comprising case so that movement of the case away from said traveling hook means for opening the leading end stationary hook means opens its trailing end closure closure flap of a case emerging from said plow means.

2. Flap opening apparatus for rectangular cases of the type provided with closure flaps hinged to the top edges the type provided with closure flaps hinged to the top of each wall, said apparatus comprising, in combination: edge of each wall, said apparatus comprising, in com- (a) Conveyor means for advancing the cases in an bination:

upright position with their closure flaps folded in- (a) Conveyor means for advancing the cases In an Ward in at least partial overlapping relation; upright position with their closure flaps folded m- (b) Plow means disposed over said conveyor means ward in at least partial overlapping relation;

to engage the side closure flaps on the case walls (b) Plow means disposed over said conveyor m ans extending parallel with the conveyor travel when to en age the side closure flaps on the case Walls such flaps are in a partially raised position; tending parallel with the conveyor travel when such (c) A side flap opening mechanism ahead of said plow flaps are in a partially raised position;

means for partially raising the side closure flaps of (c) Means ahead of said plow means for partially 4. Flap opening apparatus for rectangular cases of the cases, said mechanism including means for mothat movement of the case away from said stationary hook means opens its trailing end closure flap.

raising the side closure flaps of the case, said means mentarily arresting forward motion of a case being including an elongate rod disposed above said Concarried by said conveyor means and partially opening veyor means in substantially parallel alignment Wi h one of its side flaps, and means for then moving the conveyor travel and blower means disposed the case laterally and partially opening its other side along said elongate rod for directing air jets in an flap; and angularly downward direction and laterally from (d) An end flap opening mechanism behind said plow each side of said elongate rod, said elongate rod be- Ineans, said end flap opening mechanism comprising ing ubstantially straight over most of its length and traveling hook means for opening the leading end having its forward end curved generally upward in closure p of a Case merging from Said P means, a skew angle with respect to cases on said conveyor and rotatably mounted Stationary hook means fOf means, said rod being disposed at such elevation that engaging The trailing Closure 611d fl p 0f the 3 6 0 it is only slightly above the cases on said conveyor means when the flaps of the cases are completely closed, said rod being disposed laterally with re- 3. Flap opening apparatus for rectangular cases of the type provided with closure flaps hinged to the top edges of each wall, said apparatus comprising, in combination: (a) Conveyor means for advancing the cases in an spect to said cases so as to be directly over one of the side flaps of the cases on said conveyor means; (d) Means for arresting forward motion of a case on said conveyor means below said elongate rod upright position with their closure flaps folded inward in at least partial overlapping relation;

(b) Plow means disposed over said conveyor means to engage the side closure flaps on the case walls exand then moving the case laterally on said conveyor means toward said elongate rod, whereby as the other side flap of the case approaches the elongate rod the air jets emanating from said blower means cause partial opening of said other side flap, further lateral movement of the case urging said other side over the elongate rod so that the elongate rod and the blower means support said other side flap in the partially opened condition, the air jets emanating from the blower means being directed angularly and then moving the case laterally on said conveyor means toward said elongate rod, whereby as the other side flap of the case approaches the elongate rod the air jets emanating from said blower Ending pa wi h p z yqr travel when Such means cause partial opening of said other side flapi P are In 3 P Y false POSltlOh; further lateral movement of the case ur g sai ai h l 0f iip f i P ia y Taisother side over the elongate rod so that the elgnmg 5 S1 6 C Osure P 0 l 6 case, 531 means ate rod and the blower means su ort said 0t of including an elongate rod disposed above said conr sid fl i th partially opened cgiidtion, the air veyor means in substantially parallel alignment with jets emanating f the blower means being 1- the Conveyor travel and IhlOWfiI' means disposed rected angularly downward into the case beneath along Said elongate directing air j in an said one side flap as the other side flap rides up over ancglrlilargy dtf wnwlardl dll'ictlOIld anddlatirallyt f said elongate rod to thereby czkuse gartiallopening 05 51 e o e onfga e To Sal e Onga e To said one side flap, and means or t en re easing sai i ap g v h Over ofuits s g case to allow it to be Carrier; for glen releasing said 1 S Var e11 Curve genera Y UPWaT case to allow it to be Carrie y sai conveyor means in a skew angle with respect to cases on said conveyor into d l means; d means, said rod being disposed at such elevation that (6) A d fl p gening e ha i m behind said plow it is only slightly above the cases on said conveyor {mans Said f fla Openingmechanism i means When the p of the cases are completely 6O ing traveling hook means fo r opening the leading closed, said rod being disposed laterally with respect end closure fl f a case emerging from said plow Pd 2 t 1: as to be j over the means, and rotatably mounted stationary hook (5 1346355 for reZiiglOllLarfillZL12 means merging the filing and flap on said conveyor means below Said elongate rod the case so that movement of the case away from said stationary hook means opens its trailing end closure flap.

of each wall, said apparatus comprising, in combination:

(a) Conveyor means for advancing the cases in an upright position with their closure flaps folded inward in at least partial overlapping relation;

(b) Plow means disposed over said conveyor means to engage the side closure fiaps on the case walls asrasaa An elongate rod disposed above said conveyor means and in substantially parallel alignment with the conveyor travel, said rod being substantially to I toward said elongate rod, whereby as the other side flap of the case approaches the elongate rod the air jets emanating from said blower means cause partial opening of said other side flap, further lateral movement of the case urging said other side flap over the straight over most of its length and having its forelongate rod so that the elongate rod and the blower r ward end curved generally upward in a skew angle means support said other side flap in the partially with respect to cases on said conveyor means, said Opened condition, the air jets emanating from. the rod being disposed at such elevation that it is only blower means being directed angularly downward slightly above the cases on said conveyor means into the case beneath said one side flap as the other when the flaps of said cases are completely closed, side flap rides up over said elongate rod to thereby said rod being disposed laterally with respect to partially open said one side fiap; and

cases approaching it on said conveyor means so as (f) an end flap opening mechanism behind said plow to be directly over one of the side flaps of the cases means, said end flap opening mechanism comprising on said conveyor means; traveling hook means for opening the leading end (d) Blower means disposed along said elongate rod closure flap of a case emerging from said plow means,

for directing air jets angularly downward and and rotatably mounted stationary hook means for later-ally from each side of said blower bar, said engaging the trailing closure end flap of the case so blower means projecting slightly below said elonthat movement of the case away from said stationary gate rod to depress said one side flap to a position hook means opens its trailing end end closure flap.

7. Apparatus for opening the side closure flaps of rcctangular cases of the type provided with closure flaps hinged to the top edges of each wall, said apparatus comprising, in combination:

(a) conveyor means for advancing the cases in an slightly below the other side flap of a case on said conveyor means beneath said elongate rod;

(e) Means for moving a case laterally on said conveyor means as it passes beneath said elongate rod to bring the other side flap of the case closer to 2 said elongate rod, whereby as said other side flap approaches the elongate rod the air jets emanating from said blower means cause partial opening of said other side fiap, further lateral movement of the case urging said other side flap over the elongate rod so'that the elongate rod and the blower means support said other side flap in a partially opened condition, the air jets emanating from the blower means being directed angularly downward into the case beneath said one side flap as the other side flap rides up over said elongate rod to thereby partially open said one side flap; and

(f) An end fiap opening mechanism behind said plow means, said end flap opening mechanism including upright position with their closure flaps folded inward in at least partial overlapping relation;

(b) plow means disposed over said conveyor means to engage the side closure flaps on the case walls extending parallel with the conveyor travel when such flaps are in a partiallyraised position; and

(c) a said flap opening mechanism ahead of said plow means for partially raising the side closure flaps of the cases, said mechanism including means for momentarily arresting forward motion of a case being carried by said conveyor means and partially opening one of its side flaps, and, means for then moving the case laterally and partially opening its other side flap.

traveling hook means for opening the leading end 40 closure flap of a case emerging from said plow means. 6; Flap opening apparatus for rectangular cases of the type provided with closure flaps hinged to the top edges of each wall, said apparatus comprising, in combination: (a) conveyor means for advancing the cases in an upright position with their closure flaps folded inward in at least partial overlapping relation; (b) plow means disposed over said conveyor means 8. Apparatus for opening the side closure flaps of rectangular cases of the type provided with closure flaps hinged to the top edges of each wall, said apparatus comprising, in combination:

(a) conveyor means for advancing the cases in an upright positions with their closure fiaps folded inward in at least partial overlapping relation;

(b) plow means disposed over said conveyor means to engage the side closure fiaps on the case walls extending parallel with the conveyor travel when such to engage the side closure flaps on the case walls extending parallel with the conveyor travel when such flaps are in a partially raised position;

(0) an elongate rod disposed above said conveyor means and in substantially parallel alignment with the conveyor travel, said rod being substantially straight over most of its length and having its forward end curved generally upward in a skew angle with respect to cases on said conveyor means, said rod being disposed at such elevation that it is only flaps are in a partialy raised position; and

(c) a side fiap opening mechanism ahead of said plow means for partially raising the side closure flaps of the cases, said mechanism including means for arresting motion of a case on said conveyor means and partially opening one of its side flaps, means for then moving the case laterally, partially opening its other side flap, and then releasing said case to allow it to be carried by said conveyor means into said plow means.

slightly above the cases on said conveyor means when the flaps of said cases are completely closed, said rod being disposed laterally with respect to cases approaching it on said conveyor means so 9. Flap opening apparatus for rectangular cases of the type provided with closure flaps hinged to the top edges of each wall, said apparatus comprising, in combination:

(a) conveyor means for advancing the cases in an ,up-

as to be directly over one of the side flaps of the right position with their closure flaps folded inward cases on said conveyor means; in at least partial overlapping relation;

(d) blower means disposed along said elongate rod (b) plow means disposed over said conveyor means for directing air jets angularly downward and lateralto engage the side closure flaps on the case walls exly from each side of said blower bar, said blower tending parallel with the conveyor travel when such means projecting slightly below said elongate rod flaps are in a partially raised position; to depress said one side flap to a position slightly (c) means ahead of said plow means for partially below the other side flap of a case on said conveyor raising the side closure fiaps of the case, said means means beneath said elongate. rod; including an elongate rod disposed above said con- (e) means for arresting forward motion of a case veyor means in substantially parallel alignment with on said conveyor means below said elongate rod and the conveyor travel and blower means disposed along then moving the case laterally on said conveyor means said elongate rod for directing air jets in an angular- 1y downward direction and laterally from each side of said elongate rod, said elongate rod being substantially straight over most of its length and having its forward end curved generally upward in a skew angle with respect to cases on said conveyor means, said rod being disposed at such elevation that it is only slightly above the cases on said conveyor means when the flaps of the cases are completely closed, said rod being disposed laterally with respect to said cases so as to be directly over one of the side flaps of the cases on said conveyor means; and

(d) means for arresting forward motion of a case on said conveyor means below said elongate rod and then moving the case laterally on said conveyor means toward said elongate rod, whereby as the other side flap of the case approaches the elongate rod the air jets emanating from said blower means cause partial opening of said other side flaps, further lateral movement of the case urging said other side over the elongate rod so that the elongate rod and the blower means support said other side ilap in the partially opened condition, the air jets emanating from the blower means being directed angularly downward into the case beneath said one side flap as the other side flap rides up over said elongate rod to thereby cause partial opening of said one side flap, and means for then releasing said case to allow it to be carried by said conveyor means into said plow means.

stantially horizontal plane in an upright position with its side closure flaps open and with its leading'end closure flap folded inwardly to a substantially closed position; and

(b) Traveling hook means disposed above said conveyor means, said traveling hook means including an elongate bent arm defining a lower end portion extending in a forward and slightly downward direction, said arm being rigidly secured at its upper end to rotatably mounted lever arm means constrained for movement along a predetermined sinuous path between first and second positions in axial alignment above said conveyor means, the lower end portion of said arm being slightly behind and slightly'above the closed leading end flap of said case when said 'case is at a predetermined position on said conveyor means with said arm in said first position, blower means for directing an air jet angularly downward into the case beneath its leading end flap when the case is at said predetermined position on said conveyor means to thereby slightly raise its leading end flap sufiiciently so that the edge of the flap is slightly above the projecting tip of the lower end portion of said arm, and means for selectively moving said lever arm means along said predetermined path from said first position to said second position when said case reaches said predetermined position on said conveyor means, the rate of movement of said lever arm from said first position to 10. Apparatus for partially opening the side closure ward in at least partial overlapping relation;

(b) An elongate rod disposed above said conveyor means and in substantially parallel alignment with the conveyor travel, said rod being substantially straight over most of its length and having its forward end curved generally upward in a skew angle with respect to cases on said conveyor means, said rod being disposed at such elevation that it is only slightly above the cases on said conveyor means when the flaps of said cases are completely closed, said rod being disposed laterally with respect to cases approching it on said conveyor means so as to be directly over one of the side flaps of the cases on said conveyor means;

c) Blower means disposed along said elongate rod for directing air jets angularly downward and laterally from each side of said blower bar, said blower means projecting slightly below said elongate rod to depress said one side flap to a position slightly below the other side flap of a case on said conveyor means beneath said elongate rod; and

((1) Means for arresting forward motion of a case on said conveyor means below said elongate rod and then moving the case laterally on said conveyor means toward said elongate rod the air jets emanating from said blower means cause partial opening of said other side flap, further lateral movement of the case urging said other side flap over the elongate rod so that the elongate rod and the blower means support said other side flap in the partially opened condition, the air jets emanating from the blower means being directed angularly downward into the case beneath said one side flap as the other side flap rides up over said elongate rod to thereby partially open said one side flap.

30 said second position being graeater than the rate flaps on rectangular cases of the type provided with of movement of said case 'on said conveyor means, closure flaps hinged to the top edges of each wall, said whereby the lower end portion of said arm engages apparatus comprising, in combination: the underside of the leading end flap of said case (a) Conveyor means for advancing the cases in an and rotates it to a fully opened position.

upright position with their closure flaps folded in- 35 12. Apparatus for opening the leading end flap of a rectangular case of the type provided with closure flaps hinged to the top edges of each wall, said apparatus comprising:

(a) Conveyor means for advancing the case in a substantially horizontal plane in an upright position with its side closure flaps open and with its leading end closure flap folded inwardly to a substantially closed position;

(b) Traveling hook means disposed above said con veyor means, said traveling hook means including an elongate bent arm defining a lower end portion extending in a forward and slightly downward direction, said arm being rigidly secured at its upper end to rotatably mounted lever arm means constrained for movement along a predetermined sinuous path between first and second positions in axial alignment above said conveyor means, means for momentarily arresting forward motion of a case at a predetermined position on said conveyor means so that when said arm is in said first position said lower end portion slightly behind and slightly above the closed leading end flap of said case, blower means for directing an air jet angularly downward into the case beneath its leading end flap when the case is at said predetermined position on said conveyor means to thereby slightly raise its leading end flap sufliciently so that the edge of the flap is slightly above the projecting tip of the lower end portion of said arm, and means for selectively moving said lever arm means along said predetermined path from said first position to said second position whereby the lower end portion of said arm engages the underside of the leading end flap of said case and rotates it a fully opened position.

13. Flap opening apparatus for rectangular cases of the 11. Apparatus for opening the leading end flap of a rectangular case of the type provided with closure flaps hinged to the top edges of each wall, said apparatus comprising:

(a) Conveyor means for advancing the case in a subtype provided with closure flaps hinged to the top edges of each wall, said apparatus comprising, in combination: conveyor means for advancing the cases in an upright position with their closure flaps folded inward in at least partial overlapping relation; plow means disposed over said conveyor means to engage the side closure flaps on the case walls extending parallel with the conveyor travel when such flaps are in a partially raised position; a side flap opening mechanism ahead of said plow means for partially raising the side closure flaps of the cases andvmaintaining them in the partially raised position as the cases are carried by said conveyor means into engagement with said plow means; and an end flap opening mechanism behind said plow means, said end flap opening mechanism comprising traveling hook means for opening the leading end closure flap of a case emerging from said plow means, and rotatably mounted stationary hook means for engaging the trailing closure end flap of the case so that movement of the case away from said stationary hook means'opens its trailing end closure flap, said traveling hook means including an elongate bent arm defining a lower end portion extending in a forward and slightly downward direction, said arm being rigidly secured at its upper end to rotatably mounted lever arm means constrained for movement along a predetermined sinuous path between first and second positions in axial alignment above said conveyor means; means for momentarily arresting forward motion of a case at the flap is slightly above the projecting tip of the lower end portion of said arm, and means for selectively moving said lever arm means along said predetermined path from said first position to said second position whereby the lower end portion of said arm engages the underside of the leading end flap of said case and rotates it to a fully opened position.

References Cited UNITED STATES PATENTS 3,241,292 3/1966 Berney 53-382 3,241,292 3/1966 McIntyre 53-382 3,309,842 3/1967 Arnett 53-382 TRAVIS S. MCGEHEE, Primary Examiner. 

